Since Colin Johanson 2013 updated has planed out, ArenaNet announced the free transfer service is coming to an end on Jan 28th immediately! As transfer serveice needs to pay for a certain amount of precious stones. So ArenaNet closed the free transfer service, the mode of visitors will be opened at the same time.
Visitors mode could have you experienced in other server, steps are as follows:
Select the "World Selection" in the task selection interface
Select a server, then click the username "Guest"
Then you can be a tourist in the new server
Visitors mode restrictions:
Visitors mode can only be implementationed in the same region server. That means the American server cannot go to Europe server as visitors.
Visitors can't attend WvW, if you have to go WvW, you will be moved back to your original server.
You can be tourists in two server at the same time. Whenever you visit a server, the server will be the server you choosed in the next 24 hours. After 24 hours, you can choose as a visit to other server.
If you choose a full server to visit, then you may directly to other branch server.
Because of the open with visitors model, free transfer service is going to stop:
The gem transfer service fee will be decided by the server current population, and the server is full, then that need more stones.
The server is turned 7 days
The full sever can not been transferred. Source:http://www.gw2gold.net/news/97_5373_guild-wars-2-visitors-system-has-been-online#.UQHx6UTAyEQ